Slow copy speeds (thunderbolt/usb3) trying to recover drives.

Drobo second generation was unmountable after power failure. Migrated drives to new 5D enclosure. Bought second 5D enclosure and filled with new drives for copy of 6.5TB of data. The copy is reporting it will take 1511 hours (62 days) and the read speeds are reporting 1.5MB/sec using Data Rescue 3.

I need to figure out how to make this copy go faster.

Details from dialog with tech support:
Almost in the home stretch I hope. Here’s the situation. To expedite the copy of the files I migrated the 4 drives with my data into the 5D that has the defective fan and connected the new 5D I received yesterday and installed all new drives.
Both drobos are connected via thunderbolt (the new drive) and USB 3.0 (the old drives) respectively. In order to ‘see’ / mount the old drives I first have to kill the process fsck_hfs process from activity monitor before it will mount the old drives.

Per earlier calls I purchased DiskWarrior and Data Rescue 3.
Here’s the thing. The reading of the old drives is taking tremendously long. As you can see from the screenshot below. I initiated a data recovery and the predicted time is 62 days (1511 hours) which just isn’t viable or realistic to keep that uptime to completion.

You can see that even though we’re running over USB 3.0 the Data read/sec is only 1.5MB/sec where we should be seeing 10x that throughput. It does occasionally increase by a few MB/s but usually closer to the number shown.

So…I could really use some expert help on how to best get the data off these drives and on to the new drobo. Is there anyone who can help?


Reading your post, you mentioned that you are using the thunderbolt interface on the first DROBO, and you are using the USB 3.0 connection for the other DROBO. Did you try daisy chaining the devices, so that both are using Thunderbolt? I could see where you may see better transfer speeds if you tried daisy chaining the two with the thunderbolt ports. Not sure if that is a possible resolution or not. You definately should be seeing better throughputs on the USB 3.0 connection, but if you can, I may advise taking advantage of the thunderbolt interface and daisy chaining the two DROBOs together.

Good suggestion, I’ll try the daisy chain approach once I can find a thunderbolt cable!